WO2013041450A1

WO2013041450A1 - Sharpening device

Info

Publication number: WO2013041450A1
Application number: PCT/EP2012/068033
Authority: WO
Inventors: Horst Löhnert; Thomas TAKACS
Original assignee: Friedr. Dick Gmbh & Co. Kg
Priority date: 2011-09-22
Filing date: 2012-09-14
Publication date: 2013-03-28
Also published as: EP2758211A1; EP2758211B1; DE102011083177A1

Abstract

The invention relates to a sharpening device (10) for the blade of a cutting tool, comprising a plate-shaped base body (12) which has a guide slot (14) for a blade to be sharpened. Sharpening bars (20, 22) are pivotably mounted on the base body, on both sides of the guide slot (14). The sharpening bars (20, 22) each have two sharpening bar arms (20a, 20b, 22a, 22b) that are connected to each other at one end, wherein the sharpening bars (20, 22) can pivot out of their respective rest position by means of a pressure against an elastic return spring force created by an elastic deformation, in particular torsion, of the sharpening bars (20, 22) when the blade is introduced into the guide slot (14). The sharpening bars (20, 22) grip the base body (12) in each case with their two sharpening bar arms (20a, 20b, 22a, 22b), wherein the sharpening bars (20, 22) are, according to the invention, each pivotably mounted on the base body (12) with only one of their sharpening bar arms (20a, 22b) and are only supported on the base body (12) by the other respective sharpening bar arm (20a, 22b).

Description

Schärfvorrichtunq

The invention relates to a sharpening device for the blade of a

Cutting tool.

The blades of cutting tools, especially knives, are subject in use in the area of their cutting a high mechanical stress, by which the cutting edges lose their cutting ability, ie dull. In practice, the blades must therefore be reground at regular intervals to maintain their cutting performance. Between such grinding work, the blade, especially in professional use, usually resharpened by peeling off the blade on a sharpening steel or a sharpening device with crossed sharpening. With such a removal of the blade, an undesired ridge formed on the cutting edge of the blade is directed, whereby the edge retention of the blade increases noticeably. From EP 1260 318 Bl a sharpening device with crossed sharpening bars has become known which has a plate-shaped main body with a guide slot for a blade to be resharpened. The sharpening brackets are bent in a U-shape and articulated on both sides of the guide slot on the base body so that the sharpening brackets can be deflected from their rest position by a pressure of a blade inserted into the guide slot relative to the base body. The sharpening brackets are designed as torsion spring elements and each have two sharpening arm arms, which are connected to one another at one end. At the free end of both Schärfbügelarme a sharpening bracket each angled portions are provided which form hinge axes. These joint axes are each freely rotatably arranged in mutually offset installation openings of the base body in order to achieve an elastic recovery of the sharpening by a torsion effect.

For the manufacture of the above-described sharpening device, the free ends of both sharpening arms of a sharpening bracket must be provided with angled portions. The bends must also be mounted in designated mounting openings of the body. This is costly from a production engineering point of view.

The object of the invention is to provide a sharpening device which overcomes the aforementioned disadvantages of the prior art.

This object is achieved by a sharpening device with the features specified in claim 1. Further advantages and advantageous embodiments of the subject invention will become apparent from the description, the claims and the drawings. In the sharpening device according to the invention, the sharpening brackets are each articulated on the base body with only one of their sharpening arm arms and are preferably supported exclusively on the respective other sharpening arm on the main body. Supporting means in the present case also a support with translatory degrees of freedom of the sharpening arm with respect to the base body. As a result, the sharpening device can be manufactured without the need for a mounting opening for the rotatable mounting of the sharpening arm to be introduced on the main body. Also unnecessary is the otherwise required bend at the free end of the other sharpening arm, which forms an axis of rotation. This allows a simplified production, installation of the sharpening device and adjustment of the sharpening bow arms relative to the guide slot. This offers time and cost advantages. The sharpening brackets extend over the plate-shaped base body with their two sharpening bracket arms. Thus, in each case a sharpening bow arm is hinged on one side of the main body and the other sharpening arm of the sharpening arm is supported on the respective other side of the main body in both sharpening arms. As a result, the sharpening device can be realized in a structurally simplified construction with a low overall height. Moreover, this is for handling the sharpening advantage and allows a smaller footprint of the sharpening device during storage and transport. Also, this may reduce the risk of injury to an operator by structures protruding excessively from the base. The arms of the sharpening arms are preferably articulated to the plate-shaped main body of the sharpening device in such a way that they can be deflected from their rest position without contact to the main body, ie, without them grinding on the base body. As a result, during the sharpening process of the blade a synchronous deflection of the two sharpening bow against the Ensured basic body of the sharpening device. This allows a reproducible and especially high-quality sharpening result of the blade.

Both sharpening straps of a respective sharpening bow can be designed to run straight at their free ends according to the invention. This simplifies the production of the sharpening bow according to the invention and also its mounting on the base plate. The sharpening brackets are arranged on the base body such that the elastically resilient restoring force is generated by an elastic deformation, in particular torsion, of the sharpening bow. The sharpening brackets are in this respect made of a material, such as a stainless spring steel, formed with a material inherent elasticity. As a result, the sharpening levers deflected out of their rest position automatically return to their idle state without permanent deformation. The sharpening brackets are thus each designed in the sense of a torsion spring element. Overall, a number of the components required for the production of the sharpening device can thereby be kept low. In addition, this also results in hygiene aspects advantages. To support the other sharpening arm on the base body, a simple linear or planar abutment is sufficient. This is preferably formed by a bolt arranged on the base body, a pin, a cross-sectionally L-shaped profile piece or the like. It is understood that the sharpening arm is secured to the body preferably against unwanted slipping of the abutment.

According to the invention, the elastic restoring force of the sharpening bow is preferably variably adjustable. As a result, on the one hand, a very uniform sharpening result of the blade relative to the two cutting edges of the blade to be sharpened can be achieved. On the other hand, the sharpness effect of the sharpening device can be adjusted as needed become. In the structurally simplest case, an abutment forming the abovementioned element (bolt, etc.) on the base body relative to the articulation point (rotary joint) of the respective Schärfbügels slidably disposed.

As is known, during a sharpening process or even during storage or transport of the sharpening device, high transverse forces can sometimes attack the sharpening bars. Such, acting transversely or orthogonal to the plane spanned by the main body level on the sharpening iron forces can lead to damage of articulation points of the sharpening on the body or the sharpening itself (bending). The sharpening device can become unusable as a result. Since the two sharpening arms of the sharpening arms each cover a front and a rear side of the base body, the brackets can at least partially rest against the base body when attacking such forces and be supported on it. This type of sharpening device is thus particularly robust against damage.

The main body of the sharpening device is preferably provided circumferentially with spaced abutment surfaces arranged for the sharpening. As a result, the rest position of the sharpening bow and its maximum deflection position relative to the base body can be defined. Due to the circumferentially arranged abutment surfaces thus eliminates structures that protrude on the front or back of the base plate from the base of a plane defined by this plane. This is, as already explained above, from the point of view of occupational safety and a low overall height of the sharpening advantage. For the purpose of a simple and safe handling of the sharpening device, the base body has at least one, preferably two, engagement recesses. In the case of two engagement openings, these are preferably arranged in each case on one side of the passage opening of the base body. As a result, the body of left and right-handed operators are used equally. In addition, the sharpening device can thereby be used in two working positions, ie with the operator facing front or back of the body. This is particularly advantageous when using sharpening arms whose sharpening bow arms differ in their surface roughness, since the blade to be sharpened can be selectively pulled off (pulled along) along the sharpening arm arms provided for a desired machining result.

The engagement recess is preferably limited for a particularly ergonomic and safe handling of a wall portion of the body, which is provided with recessed grips. The recessed grips are advantageously designed ergonomically rounded.

In practice, it has proved to be particularly advantageous if the base body has at least one, preferably two, handle portions. The grip sections preferably have an angled edge region, which forms a hand rest. As a result, the ease of handling and operating safety of the sharpening device can be increased even further and the base body can be kept particularly thin with respect to its material thickness

For stationary mounting of the sharpening device, for example on a worktop, the base body is preferably provided with a fastening device. The fastening device can In particular, have a tongue-shaped or flange-like attachment extension. The fastening extension can, according to the invention, have recesses for fastening means, such as bolts and / or screws, for the purposes of a rotationally secure mounting of the sharpening device on a base.

The main body and the sharpening bow are most preferably made of a stainless steel. This allows the sharpener to be used in corrosive environments without being damaged. In addition, very high hygienic standards, such as those applied in food processing plants, such as (large) kitchens, butcheries and the like, can be easily taken into account. Stainless steel offers advantages over plastics in terms of adhesion of bacteria and the formation of unwanted biofilms. In addition, the stability of said sharpening device is increased.

For the purpose of a further improved durability of the sharpening device, the main body is preferably hardened in the region of its walls bounding the guide slot, in particular nitrided.

The invention relates to a sharpening device for the blade of a cutting tool, with a plate-shaped base body having a guide slot for a blade to be sharpened. On the main body sharpening arms are pivotally hinged on both sides of the guide slot. The sharpening brackets each have two sharpening arm arms, which are connected to one another at one end, wherein the sharpening brackets can be pivoted from their respective rest position by a pressure of the inserted into the guide slot blade against an elastically resilient restoring force, by an elastic deformation, in particular Twist generated sharpening strap. According to the invention, the sharpening brackets are articulated with only one of their sharpening arm arms under contact with the main body and supported with the respective other sharpening arm exclusively on the main body.

The invention will be explained in more detail with reference to an embodiment shown in the drawing. The embodiment shown and described is not meant to be exhaustive, but rather illustrative of the description of the invention. The figures of the drawing show the subject matter according to the invention in a highly schematized manner and are not to be understood to scale.

In the drawing show;

Fig. 1: a sharpening device according to the invention for the blade of a cutting tool not shown in detail, in front view; and

FIG. 2 shows the sharpening device from FIG. 1 in a longitudinal section along the section line designated A-A in FIG. 1.

Fig. 1 shows a sharpening device 10 according to the invention for the blade of a cutting tool not shown in detail. The sharpening device 10 has a plate-shaped base body 12 which is provided with a formed as an incision in the base body 12 guide slot 14 for the blade to be sharpened of the cutting tool. The guide slot 14 extends from its inlet region 16 almost over the entire longitudinal extension L of the base body 12 and is formed by two opposing walls 18 of the main body 12 educated. In the entry region 16, the guide slot 14 is widened or widened funnel-shaped in order to facilitate the insertion of a blade to be sharpened.

On the base body 12 are on both sides of the guide slot 14 substantially U-shaped curved Schärfbügel 20, 22 hinged, which intersect in a guide slot 14 overlapping crossing point 24. The two sharpening brackets 20, 22 are arranged substantially mirror-inverted to the guide slot 14 and the same shape.

2, the sharpening device is in a along the in FIG. 1 with A-A designated cutting line guided longitudinal section reproduced. As can be seen from this illustration, the two sharpening brackets 20, 22 each have two sharpening arm arms 20a, 20b, 22a, 22b, which are connected to each other at one end via a curved back section 26 of the sharpening brackets 20, 22.

The two sharpening brackets 20, 22 each encompass the main body 12 of the sharpening device 10 with their respective sharpening arm arms 20a, 20b, 22a, 22b. In other words, in this case one sharpening arm 20a, 22a respectively covers the main body 12 at its front side 28, while another sharpening arm 20b, 22b of the sharpening arm 20, 22 covers the main body 12 respectively at its rear side 30.

As shown in Figs. 1 and 2, the two sharpening brackets 20, 22 with a free and straight end portion 32 of only one of their sharpening arms 20a, 20b, 22a, 22b rotatably mounted via attachment means 34 at articulation points 36 of the body 12. In the present case, these are the sharpening arm arms 20a and 22b. The free end portions 32 of these two sharpening arms 20a, 22b are not angled and extend into the fasteners 34, in which they are clamped.

The fastening means 34 extend through Befestigungsmittelausnehmungen not shown in detail of the base body 12 and are pivotable in this together with the respective sharpening bow 20, 22 relative to the base body 12, i. the fastening means 34 are rotatably mounted in the base body 12.

As shown in Figs. 1 and 2, the sharpening brackets 20, 22 are supported with a free and straight end portion 32 of their respective other sharpening arm 20b, 22a only on a profile projection 38 of the main body 12. That is, the free ends 32 of the sharpening bow arms 20b, 22a are not pivotally connected to the base body 12 here. The profile projections 38 each serve as an abutment for the end portions 32 of the sharpening arm 20b and the sharpening arm 22a. These two sharpening bow arms 20b and 22a rest loosely against the profile projections 38.

The sharpening bow 20 is thus articulated with its sharpening arm 20 a on the front side 28 of the base body 12 in the pivot point 36 rotatably on the base body 12. In contrast, the other sharpening arm 20b of the sharpening arm 20 is supported on the rear side 30 of the main body on the profile projection 38 shown in FIG.

The sharpening bracket 22 is pivotally hinged with its rear sharpening bow arm 22b on the back 30 of the base body 12 at the articulation point 36 shown on the left in FIG. 1 on the base body 12 and with its sharpening arm 22a on the front side 28 of FIG Base body 12 supported on the profile projection 38 of the base body 12 shown in Fig. 1.

The profile projections 38 project from the front side 28 and the rear side 30 of the main body 12 beyond the front and rear sides 28, 30 thereof and are offset relative to the corresponding articulation points 36 of the respective sharpening brackets 20, 22 on the main body 12. The profile projections 38 are welded to the base body 12 in the present case. According to an alternative embodiment, the profile projections 38 can also be punched out of the material of the base body 12 and bent in shape. According to a further embodiment, the profile projections 38 may also be formed by separate components to the main body 12, which extend through a recess of the base body 12 and which may be rotatably connected to the main body 12.

The sharpening brackets 20, 22 are pivotable relative to the base body 12 in a direction of rotation relative to the base body 12, indicated by arrows 42, by a blade inserted into the guide slot 14 from its shown rest position. The sharpening brackets 20, 22 are in their shown rest position with their curved back portions 26 on the first stop surfaces 44 of the body 12, which are formed on the outer periphery 46.

A guided along the guide slot 14 blade thus meets in the region of the intersection point 24 on the sharpening 20a, 20b and leads them in the direction of rotation 42 in its end position, not shown, in which the sharpening brackets 20, 22 respectively abut second abutment surfaces 48 of the body 12. The second stop surfaces 48 of Base body 12 are arranged in a manner corresponding to the first stop surface ends 44 on the outer periphery 46 of the base body 12. The second stop surfaces 48 are arranged spaced apart from the first stop surfaces 44. Stop structures for the sharpening, which protrude from the front or back 28, 30 of the body 12, thus unnecessary.

The sharpening brackets 20, 22 are each arranged with their two sharpening bracket arms 20a, 20b, 22a, 22b on the base body 12 such that the elastically resilient restoring force is generated by an elastic deformation, in this case a torsion, the sharpening bracket 20, 22 itself. Separate spring elements are unnecessary. When deflecting the sharpening brackets 20, 22 from the rest position in the direction 42 of the second stop surfaces 48 by means of a blade to be sharpened, the two sharpening brackets 20, 22 thus each elastically twisted. As soon as the blade is removed from the sharpening brackets 20, 22, they automatically return to their rest position.

The individual sharpening bow arms 20a, 20b, 22a, 22b of a sharpening bow 20, 22 differ in their present surface roughness in the present case. According to an alternative embodiment, the sharpening arm arms 20a, 20b, 22a, 22b of a sharpening arm 20, 22 have a surface roughness corresponding to one another, while the two sharpening brackets 20a, 20b differ from each other in their respective surface roughnesses.

The main body 12 has on both sides of the guide slot 14 cut engagement recesses 50 which are provided for engaging a sharpener 10 holding the hand of an operator. The main body 12 forms two gripping pieces 52, each having an angled outer edge portion 54. This angled Edge portions 54 each form a hand support surface 56 for a hand of an operator. At wall portions 58 of the engagement recesses 50 ergonomically rounded recessed grips 60 are formed. The base body 12 has on its outer periphery 46 on both sides of the guide slot 14 trough-shaped thumb rest 62 on.

At a (lower) end of the main body 12 facing away from the inlet region 16 of the guide slot 14, a T-shaped mounting flange 64 is arranged with recesses 66 for fastening means to rigidly arrange the sharpening device 10 on a countertop or the like.

The dimensions of the sharpener 10 are selected such that the sharpener can be held by a user without difficulty in one hand. The sharpening device 10 is made entirely of stainless steel and hardened at least in the region of the walls 18 of the guide slot 14.

The invention is not limited to the embodiments given above. Rather, variants are conceivable, which make use of the features of the invention even with fundamentally different type of execution.

Claims

claims:

1. sharpening device (10) for the blade of a cutting tool,

with a plate-shaped base body (12), the one

Guide slot (14) for a blade to be sharpened, with both sides of the guide slot (14) on the base body (12) pivotally hinged sharpening (20, 22), which intersect,

wherein the sharpening brackets (20, 22) each have two sharpening arm arms (20a, 20b, 22a, 22b) which are connected together at one end,

wherein the sharpening brackets (20, 22) are pivotable from their respective rest position by a pressure from the inserted into the guide slot (14) blade against an elastically resilient restoring force, and

wherein the elastically resilient restoring force is generated by an elastic deformation, in particular torsion, of the sharpening bow (20, 22),

characterized in that

the sharpening brackets (20, 22) respectively engage around the main body (12) with its two sharpening arm arms (20a, 20b, 22a, 22b), the sharpening brackets (20, 22) each having only one of them

Sharpening bow arms (20a, 20b, 22a, 22b) are rotatably articulated on the main body (12) and are supported exclusively on the main body (12) by their respective other sharpening arm (20a, 20b; 22a, 22b).

2. sharpening device according to claim 1, characterized in that the elastically resilient restoring force is variably adjustable.

3. sharpening device according to claim 1 or 2, characterized in that the base body circumferentially first and / or second

Stop surfaces (44, 48) for the sharpening (20, 20).

4. Sharpening device according to one of the preceding claims,

characterized in that the base body (12) has at least one, preferably two engagement recesses (50).

5. sharpening device according to claim 4, characterized in that the at least one engagement recess (50) in each case by a wall portion (58) is limited, which is provided with recessed grips (60).

6. Sharpening device according to one of the preceding claims,

characterized in that the base body (12) has a

Handle portion (52) having an angled edge region (54), wherein the edge region (54) forms a hand support surface (56).

7. sharpening device according to one of the preceding claims,

characterized in that the base body (12) at its outer periphery (46) has at least one trough-shaped thumb rest (62).

8. sharpening device according to one of the preceding claims, characterized in that the base body (12) has a

Mounting flange (64), which preferably with

Recesses (66) is provided.

9. sharpening device according to one of the preceding claims,

characterized in that sharpening device (10) is made entirely of stainless steel.